The Doors lacked a bassist, so Manzarek usually played the bass parts on a Fender Rhodes piano. His signature sound is that of the Vox Continental combo organ, an instrument used by many other psychedelic rock bands of the era. He later used a Gibson G-101 Kalamazoo combo organ (which looks like a Farfisa) because the Continental's plastic keys frequently broke, according to Manzarek.